Pass through funding from one charity to another

I have never understood why nonprofit charitable organization would raise money for their cause only to give it to another organization with different causes. It will always appear that the first organization was not really necessary. It was functioning only as a pass through, in which case you have to ask why didn't the people donate their money to the 2nd organization? Or was the 1st organization deliberately misleading the people donating them money in order to fund the other causes the people would not ordinarily donate to?